SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c896f99cc33a98af543a014cbb8ed476a834be78ac0b589ce20cc71ee454f5d9' 
  AND token = 'wqzjtjkRFpdmJJuN/k2QWjMz1TE00BPpV4WioSJNFrM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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