SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aab4a03c44d2906563a2793a62d53586945a9ef35baf493b2e8f590403152d3e' 
  AND token = 'BMGLYgxpmOQTUJaC+rgBj2n+BvPrf4FK1uNFPz/hjj0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}